Essential phospholipids and athletic performance: is there an effect

In the sports community, essential phospholipids are usually perceived as «liver support», but from time to time they are also credited with a direct effect on endurance, recovery, or strength. The editorial team examined which phospholipids have actually been studied in sport, what the research showed, and why a liver medication should not be confused with a sports supplement.

Where the expectations came from

Phospholipids are a large family of molecules, and in sports nutrition they appear under various names: lecithin, phosphatidylcholine, phosphatidylserine, phosphatidic acid, krill oil. Essential phospholipids as a medicinal product are only one of them, namely purified soy phosphatidylcholine with a high proportion of linoleic acid.

The logic of the expectations is clear: phospholipids form the membranes of muscle cells, take part in signal transmission, and phosphatidylcholine is a source of choline — the precursor of the neurotransmitter acetylcholine, which transmits the impulse from nerve to muscle. Hence the assumption that additional intake could improve the work of the neuromuscular system or recovery.

The review by Jäger, Purpura, and Kingsley (2007) in the Journal of the International Society of Sports Nutrition summarized studies of phospholipids in sport and concluded that different compounds have different evidence bases and cannot be assessed together. It is precisely this differentiated approach that we apply in this article.

Another source of expectations is marketing. «Liver» medications are often sold alongside sports nutrition, and in athletes' unofficial «protocols» they appear as a mandatory component, creating the impression that they affect performance.

Choline and endurance: the marathoners' hypothesis

In the 1980s researchers noted that the level of choline in the blood plasma of marathoners drops after a race. A short report by Conlay and colleagues in the New England Journal of Medicine (1986) described a substantial decrease in choline after the Boston Marathon. A hypothesis arose: if choline is lacking for the synthesis of acetylcholine, this may contribute to fatigue.

Subsequent work tested whether lecithin intake prevents the drop in choline levels. The study by von Allwörden and colleagues (1993) in triathletes and runners and by Buchman and colleagues (2000) in marathoners showed that taking lecithin before exertion does indeed maintain the concentration of choline in plasma.

However, maintaining the choline level is not the same as improving performance. No convincing improvement in athletic indicators was demonstrated in these works, the samples were small, and the study design did not always allow performance itself to be assessed. For short and medium exertion this hypothesis has no significance at all: no noticeable decrease in choline was observed there.

A healthy person covers their need for choline from food: eggs, liver, meat, fish, legumes. The European Food Safety Authority (EFSA) set the adequate intake of choline for adults at 400 mg per day. Athletes with a varied diet, as a rule, do not need a separate source of choline.

Other phospholipids: phosphatidylserine and phosphatidic acid

Unlike phosphatidylcholine, phosphatidylserine has been studied specifically in the sports context. The review by Kingsley (2006) in Sports Medicine described data on a possible smoothing of the hormonal stress response (cortisol) to intense exertion and separate signals regarding well-being and recovery. At the same time, the results of studies on performance are ambiguous.

Phosphatidic acid attracted attention as a possible signaling molecule of the mTOR pathway, which regulates muscle protein synthesis. The study by Hoffman and colleagues (2012) in trained men found only trends toward a greater gain in strength and muscle mass, whereas subsequent work gave contradictory results.

Important: even if there are separate positive data for phosphatidylserine or phosphatidic acid, they cannot be transferred to essential phospholipids. These are different molecules with different functions, and pharmaceutical PPC does not contain them in significant amounts.

Thus, if an athlete is interested specifically in the effect of phospholipids on performance, the relevant studies concern other compounds, not liver medications.

The athlete's «liver protection»: what the data say

The most common use of essential phospholipids in sport is not for performance but as an accompaniment to potentially hepatotoxic substances, primarily oral anabolic steroids. The editorial team has repeatedly stressed: there are no studies that would show that phospholipids prevent the cholestasis, peliosis, or liver tumors associated with these substances.

The Endocrine Society review (Pope et al., 2014) describes the hepatic complications of performance-enhancing agents as a serious problem for which there is no pharmacological prevention. The use of a «hepatoprotector» does not make such regimens safer.

Another aspect is the interpretation of tests. The work by Pettersson and colleagues (2008) showed that intense strength exertion in healthy men can significantly raise AST and ALT. An athlete who sees such results may mistakenly decide that «the liver is suffering» and begin taking phospholipids, although the cause lies in the muscles.

• To assess the liver, an athlete needs transaminases together with CK and GGT.
• Tests should be taken after several days without heavy training.
• A persistent elevation of enzymes is grounds for a doctor's consultation, not for self-treatment.

So, if an athlete's liver is genuinely damaged, phospholipids do not solve the problem, and if it is not damaged — they are not needed. In any case they do not affect athletic performance.

Status in sport and practical conclusions

Essential phospholipids are not included in the Prohibited List of the World Anti-Doping Agency (WADA) and are not doping. Taking them creates no anti-doping risks, provided the product itself is not contaminated with foreign substances, which for pharmaceutical products is unlikely.

From a safety standpoint, the medication is well tolerated, the main limitations being allergy to soy and its components. However, from the standpoint of benefit for performance there are no arguments: no evidence of effectiveness has been obtained, neither for endurance, nor for strength, nor for recovery.

For athletes who want to support liver health, the editorial team advises focusing on proven things: controlling body weight and fat percentage, minimizing alcohol, avoiding hepatotoxic substances, and being cautious with «fat burners» and plant extracts of dubious composition.

If, however, the goal is to improve performance, it is worth paying attention to supplements with a stronger evidence base: creatine monohydrate, caffeine, beta-alanine, nitrates — and to the fundamentals of training, nutrition, and sleep.

Editorial conclusions

Essential phospholipids are a medication with hepatological indications, not a sports supplement. No direct effect on athletic performance has been found in studies.

The hypothesis about choline during prolonged exertion has been partly confirmed at the biochemical level, but not at the level of performance; the data on phosphatidylserine and phosphatidic acid concern other molecules and remain contradictory.

Using phospholipids as «liver protection» against a background of hepatotoxic substances has no scientific basis and creates a false sense of safety.

The editorial team also recommends reviewing our materials on the effect of essential phospholipids on the liver and kidneys, on tests during their intake, and on meldonium and athletic performance.

References

1. Jäger R, Purpura M, Kingsley M. Phospholipids and sports performance. J Int Soc Sports Nutr. 2007;4:5.
2. Kingsley M. Effects of phosphatidylserine supplementation on exercising humans. Sports Med. 2006;36(8):657–669.
3. Conlay LA, Wurtman RJ, Blusztajn K, et al. Decreased plasma choline concentrations in marathon runners. N Engl J Med. 1986;315(14):892.
4. Buchman AL, Awal M, Jenden D, Roch M, Kang SH. The effect of lecithin supplementation on plasma choline concentrations during a marathon. J Am Coll Nutr. 2000;19(6):768–770.
5. Hoffman JR, Stout JR, Williams DR, et al. Efficacy of phosphatidic acid ingestion on lean body mass, muscle thickness and strength gains in resistance-trained men. J Int Soc Sports Nutr. 2012;9:47.
6. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Dietary Reference Values for choline. EFSA J. 2016;14(8):4484.
7. Pettersson J, Hindorf U, Persson P, et al. Muscular exercise can cause highly pathological liver function tests in healthy men. Br J Clin Pharmacol. 2008;65(2):253–259.
8. Pope HG Jr, Wood RI, Rogol A, et al. Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement. Endocr Rev. 2014;35(3):341–375.